We seek partial support for the third in a series of FASEB Summer Research Conferences on "Growth Factor Receptor Tyrosine Kinases I Mitogenesis, Morphogenesis, and Tumorigenesis", to be held in Tucson AZ from August 2 to August 7, 2003. This conference will build upon the success of the two earlier conferences held in 1999 and 2001, and continue to focus on new developments in biology and pathophysiology of important classes of growth factor receptor tyrosine kinases as they relate to mitogenesis, development, morphogenesis, tumorigenesis and tumor progression. Because of the overwhelming breadth of the tyrosine kinase field, consistent with earlier meetings we will maintain some emphasis on recent developments relevant to ErbB and Met families of receptor tyrosine kinases. However, the sessions on developmental systems have been expanded to include invertebrate receptor signaling paradigms, since these systems lead the way on understanding integrative mechanisms of receptor signaling. For these, and other unique receptor kinase signaling paradigms, we will broaden the scope beyond these receptors. A new session, including plenary talk, has been added to discuss the important and topical question of signal specification by receptor tyrosine kinases. The Scientific Program will include platform presentations by 26 invited speakers, internationally renowned leaders in their respective areas. The program will also include a significant number of oral presentations selected from the Abstracts, and also Poster Sessions to showcase work by all attendees. A Young Investigator Mini-Symposium, which was a highlight of the previous conferences, will be featured. In order to maximize scientific interactions among participants, conference attendance will be limited to 100-190 investigators including invited speakers and individuals selected from the conference applications. We will endeavor to provide a mix of established and junior investigators, with participation by women and minorities encourage. We anticipate that this conference will succeed in serving as a forum for state-of-the-art scientific interchange on growth factor receptor tyrosine kinases. It will foster new collaborative enterprises, and maintain the high standards appropriate to the FASEB Conference series.